It is obvious from Paragraph 4 that the chief cause leading to the disaster is ______.

A．anyone who regards the debate over family structure as an attack on single mothers and their children
B．anyone who believes in evidence of social-science
C．people who ignore the issue of changing family structure
D．people who respect women's right to pursue freedom and independence in children-bearing and children-rearing

A．whether we should believe in equality and diversity
B．how parents should pursue their individual happiness
C．why we should meet the needs of children for a happy family
D．how the breakup of the families threatens the well being of children